1. Field of the Invention
The present invention relates to a projector device adapted to guide light from a light source to an optical system to generate image light for magnification projection on a forward screen.
2. Description of Related Art
A conventional projector device of this type includes a casing having disposed therein a light source and an optical system including a polarization beam splitter, a polarizing plate, liquid crystal panels, a projection lens, etc. A discharge emission lamp unit such as a halogen lamp and a metal halide lamp is used as the light source.
The lamp unit includes a lamp and a reflector for reflecting light emitted from the lamp toward the optical system. The lamp is formed by enclosing a luminous body inside a quartz bulb. The lamp is cooled by a cooling unit because the lamp has a shortened life when the lamp has a temperature exceeding a limit temperature.
The reflector of the lamp unit has a reflecting portion having a quadratically curved reflecting surface for reflecting the light emitted from the lamp toward the optical system, and a plurality of side walls extending from the reflecting portion toward the optical system to surround the lamp. The cooling unit is attached to a first side wall of the plurality of side walls.
A blower opening for introducing air delivered from the cooling unit toward a light emitting portion of the lamp is formed on the first side wall of the reflector, while a discharge opening for discharging the high temperature air outside the reflector is provided on a second side wall opposed to the first side wall in a position opposed to the blower opening (see JP 7-281296, A). Because the lamp could explode due to long use, the blower opening and the discharge opening are constituted of a plurality of small holes with a small opening area in order to prevent broken pieces of the lamp from flying outside the reflector upon the explosion.
The lamp in the above conventional lamp unit is cooled by the air introduced inside the reflector through the blower opening and flowing around the lamp. However, the above conventional lamp unit has a problem of the lamp being unable to be sufficiently cooled despite a sufficient air volume being given inside the reflector through the blower opening.